<!DOCTYPE HTML>

<html>
<head>
<title>WebGL Context Restored Test</title>
<style type="text/css">
.nomargin {
  margin: 0px auto;
}
</style>

<script>
function sendResult(status, detail) {
  console.log(detail);
  if (window.domAutomationController) {
    window.domAutomationController.send(status);
  } else {
    console.log(status);
  }
}

// This test kills the GPU process, which takes some time to recover,
// so give it a few seconds before proceeding.
var numFramesBeforeEnd = 180;

var gl;

function clearToRed() {
  gl.clearColor(1.0, 0.0, 0.0, 1.0);
  gl.clear(gl.COLOR_BUFFER_BIT);
}

function clearToGreen() {
  gl.clearColor(0.0, 1.0, 0.0, 1.0);
  gl.clear(gl.COLOR_BUFFER_BIT);
}

function main() {
  var canvas = document.getElementById("c");
  gl = canvas.getContext('webgl');
  if (!gl) {
    sendResult("FAILURE", "WebGL context not supported");
    return;
  }

  canvas.addEventListener('webglcontextlost', contextLostHandler, false);
  canvas.addEventListener('webglcontextrestored', contextRestoredHandler, false);

  // Clear the canvas to red. The harness will then crash the GPU
  // process for us, the context will be restored, and the canvas will
  // be cleared to green.  Ensure this mechanism is working correctly.
  clearToRed();

  // Sending READY will make the GPU process crash.
  sendResult("READY");
}

function contextLostHandler(e)
{
  console.log("Context lost");
  e.preventDefault();
}

function contextRestoredHandler()
{
  console.log("Context restored");
  clearToGreen();
  waitForFinish();
}

function waitForFinish()
{
  if (--numFramesBeforeEnd == 0) {
    sendResult("SUCCESS", "Test complete");
  } else {
    window.requestAnimationFrame(waitForFinish);
  }
}
</script>
</head>
<body onload="main()">
<canvas id="c" width="300" height="300" class="nomargin" style="position:absolute; top:0px; left:0px;"></canvas>
</div>
</body>
</html>
